20891299 has 8 divisors (see below), whose sum is σ = 24543792. Its totient is φ = 17531040.

The previous prime is 20891293. The next prime is 20891333. The reversal of 20891299 is 99219802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20891299 - 2¹⁵ = 20858531 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20891293) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72904 + ... + 73189.

It is an arithmetic number, because the mean of its divisors is an integer number (3067974).

Almost surely, 2^20891299 is an apocalyptic number.

20891299 is a deficient number, since it is larger than the sum of its proper divisors (3652493).

20891299 is a wasteful number, since it uses less digits than its factorization.

20891299 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146117.

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 20891299 is about 4570.7000557901. The cubic root of 20891299 is about 275.4155656420.

The spelling of 20891299 in words is "twenty million, eight hundred ninety-one thousand, two hundred ninety-nine".